Eclipse UDC2500 Limit, Manual

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Modbus RTU Function Codes
90 UDC2500 Universal Digital Limit ControllerProduct Manual 8/05
9.3 Function Code 20 (14h) - Read Configuration Reference Data
Description
Function code 20 (14 Hex) is used in this instrument to read information stored in its
configuration database. Each configuration item is explicitly addressed by a file number
and register address. IEEE 32-bit floating point and 16-bit integer formats are supported.
Request and Response Formats
The Request and Response formats for Function code 20 (14 Hex) are shown below.
Details for each block reference follow.
Request Message Format
Slave
Address
Byte
Count
Reference
Type
Function
Code 14 Reference
Type
File
Number
Register
Count
Register
Address
Reference
Type
File
Number
Register
Count
Register
Address
CRC
Data CRC
Data
Response Message Format
Slave
Address
Byte
Count
Reference
Type
Function
Code 14
Reference
Type
Data
Reference
Type
Data
Byte
Count
Data Data
Data
Data
Byte
Count
Data Data Data Data
CRC
Data CRC
Data
For Infrared Transactions, add three BOFs (C0hex) at the beginning of each message and
one EOF (FFhex) at the end of each message.
Byte Count
The Byte Count equals the number of bytes transmitted in either the request or response
message and will be the minimum number required to transmit all requested data.